How to Trim an Opening for Your Attic Stairs

Enlarge the opening and hang pull-down stairs according to the manufacturer's instructions.

Climbing a moveable ladder and entering the attic is a tricky proposition. Ladders aren't completely stable and the access hole is only so big. Typically, the floor above is precarious -- a series of joists with nothing but wall sheathing on the underside, forming the ceiling of the room below. In reality, what usually happens is that only the space in arm's reach of the opening gets used. A pull-down attic stairway makes all the difference. Once you have stairs, you can floor the attic and store things from wall to wall. Cutting and framing the space is actually the simplest portion of the job.

1

Inspect the room to decide the most convenient location for the attic stairs for a new stair installation or enlarge a small access opening. Knock on the ceiling or use a stud finder to find the wood framing forming the attic floor. Alternatively, work from the attic where the framing is completely visible.

2

Measure and mark the stair opening dimensions required from either the room below or from the attic above. Consult the stair manufacturer's installation instructions to obtain the opening measurements. Check to ensure that the area is clear of wiring, ducts and pipes before determining the exact stairway placement. Move insulation aside if necessary. Typically, if there's already a small access hole, which will be free of obstructions. Relocate the opening as necessary to clear objects or run between the framing.

3

Slice through the ceiling sheathing using a utility knife or a jigsaw for wood ceiling covering. Pry away the sheathing to reveal the framing members above. Work carefully to avoid slicing too deeply, biting into the framing, or tearing the sheathing past the removal.

4

Saw through the framing with a reciprocating saw. Work from beneath or above, as you feel comfortable. Proceed carefully to avoid falling with the saw, a potentially fatal mistake.

5

Measure and cut two boards of the same size as the ceiling joists is preferable. Insert the boards at either end of the opening between the main joists. Check the spacing before securing the last board. Nail through the joists and into the new board ends with two or three nails. These boards form the opening header. Measure from corner to corner, diagonally, and compare the measurements to ensure the opening is square.

6

Cut trimmers, which are boards running between the headers, parallel to the joists, to narrow the opening if necessary. In some cases, the opening is wider than the distance between joists, and narrowing the opening with trimmers ensures a precise fit. Nail through the trimmers into the headers, driving the nails at an angle, a process referred to as "toe-nailing." If the trimmer is against a joist, nail through the trimmer into the joist as well.

7

Measure and cut short blocks to run between the trimmers and joists, one every 12 inches, to further stabilize the opening. Nail in place to secure.

Things You Will Need

Tape measure

Utility knife

Reciprocating saw

Carpenter's square

Boards

Hammer

10d nails

Tip

Lay a few boards in the attic, on top of the joists, to provide a walkway.

Proceed with the stair installation, according to the product directions, once the opening is trimmed.